Compressed-air-cushion block.



No. 886,193. PATENTED APR. 28, 1908. G. C. DE WITT.

COMPRESSED AIR CUSHION BLOCK.

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* y W QZM nnrrnn STATES PATENT orrion.

CLINTON C. DE WITT, OF ST. LOUIS, MISSOURI, ASSIGNOR OF ONE-HALF TO FRANK L. AYMOND,

OF ST: LOUIS, MISSOURI.

COMPRESSED-AIR-CUSHION I LOOK.

Specification of Letters Patent.

Patented April 28, 1908.

Application filed November 12, 1907. Serial No. 401,898.

' a specification containing a full, clear, and

exact description, reference being had to the accompanying drawings, forming a part hereof.

My invention relates to a compressed air cushion block to be used on the upper end of concrete piling when the same is being driven into the ground, and my present invention is an improvement on a similar device for which application for Letters Patent in the United btates were issued to me December .10, 1907, No. 873,517. 7

The object of my present invention is to generally improve and simplify the construction of the device shown and described in the application above referred to, and to provide means whereby a body of liquid is located in the chamber between the two members forming the block in order that the air cushion in said chamber may be readily varied to suit different conditions.

To the above pur oses, my invention consists in certain nove features of construction and arrangement of parts, which will be hereinafter more fully set forth, pointed. out in the claims, and illustrated in the accompanying drawings, in which Figure 1 is a perspective view of a cushion block of myimproved construction; Fig. 2 is a vertical section taken on the line 2-2 of Fig. 1 Fig. 3 is a horizontal section taken on the line 33 of Fig. 2'; Fig. 4 is an enlarged section illustratim the acking rings utilized between the members fiirming my improved block.

Referring by numerals to the accompanying drawings :1 designates the up er member of the block, which is in the form of a hollow'cylinder with the upper end closed, and there being a recess 2 formed in the top of said member, and which recess is adapted to receive a block of wood, or analogous material, 3 which acts as an anvil or striking surface for the hammer of the ile driver.

Formed integral with an on 0 posite sides of the member 1 are the ve rtica ly disposed pairs of flanges 4, which serve as guides and engage the vertically disposed uprightsof the pile driver frame when the device is in use.

Formed integral with the member 1, adjacent the upper end thereof, are lugs 5, to

which may be attached chains or cables utilized in hoisting the block into position for use.

' Formed through the wall of the member 1 and communicating with the upper end of the chamber 6, within said member, is an aperture 7, which is normally closed by a screw plug 8 {and formed through the wall, a short distance below this aperture 7, is a second a erture 9, and fitted therein is a short nipp e 10, provided with a valve or stop cock 11.

The ower or piston member 12 of the block is in the form of a cylinder adapted to fit snugly within the cylindrical member 1, and formed in the under side olithe bottom of said member is a recess 13, adapted to re' ceive the upper end of the piling; and formed on the o posite sides of the lower portion of the mem er 12 are the pairs of vertically disposed guide ribs 14, which, when the device is in use, are in alinement with the'guides 4 and bear on the uprights oi the pile driver frame. y

Formed integral with the lower portion of the member 12 are lugs 15,.similar to the lugs 5, and which are utilized when the block 12 is hoisted into position for use.

The block 12 is preferably cored out to lighten its weight, and the upper end of said block is cut away on its criphery, as designated by 15; and seated in this cut away space-is a pair of on shaped packing rings 16', of leather, or ana ogous material, which are held in place by a pair of metal rings "18,

the upper one of which is provided with a flange 19, which projects over the top' edge of the block 12 and receives screws 20, which fasten said upper ring to the block.

The top edges of the packing rings are beveled, as designated by 21, in order that enga e on said beveled edges will tend to tightly pack the rings against the surface of the air chamber 6 in the block 1.

When my im roved block is made ready for use, a heavyliquid. such as oil or glycerin is delivered to the air chamber 6 through the nipple 10, open valve 11 and a Jerture 9, and after a sufiicient quantity of liquid is delivered to said chamber, air is pumped into the any air or liquid under pressure which may v the u per end of the ile, thuspreventing the g chamber, and when the valve 11 is closed, the air within the chamber 6 and above the liquid provides a suitable pneumatic cushion when compressed by the action-of the pile driver hammer on the member 1 of the device.

By removing the screw plug 8 a portion of the air trapped in the chamber 6is allowed to escape and, therefore, the position of the memberv 1 upon the member 12 can be accurately regulated and the .cubic area of the air cushion varied as desired.

The hammer of the pile driver strikes upon the black 3 and in so doing moves the member 1 downward upon the member 12 ,I thus compressing the air within the chamber 6; and the cushioning eiiect obtained by this compression breaks the force of the compact between the lower end of the member 12 and to o the pile from eing shattered as a re sut of the driving blows of the hammer.

The oil, or other liquid, which partially fills the air chamber between the members of the block provides a very effective packing; and, together with the packing rings, 16, prevents the escape of air while under com ression within the chamber 6; and where oiihs used as the liquid within the air chamber, the en-. gaging faces of the two members of the block are thoroughly lubricated.- I claim 1. A. cushion block of the class described, comprising a pair of telesco ing members, there being a chamber forme betweensaid members, a flexible acking ring arranged in one of the bearing is here and a solid ring. engaging the flexible ring for maintaining thesame in position.

taiinng the same in position.

ces of one of the mem- .2. A cushion block of the elass described,

comprising a .pair of telesco ing members, 40

there being a chamber forme between said. members, flexible packing rings arranged on 'the upper end of the innermember, solid rings engaging the flexible rings for main- 3. 'A cushion block, comprising .a air of telescoping members, between whic is formed a flexible chamber, a packing ring arranged in the bearing face of one of the 1 members, a solid ring engaging theflexible 5 ring to maintain the same in position, and means whereby fluid is delivered to and allowed to dischar e from the air chamber.

' 4. A cushion b ock, cemprising a of telescopi'ng members, between Whic formed a chamber, there being a recess formed in the under side of the lower one of the telescoping members, a flexible acking ring arranged in the bearing face oi -one of the members, and a solid ring engaging the 0 flexible iii to maintain the same in position.

5. A 011511011 block, com rising a pair of telescoping members, a flexi le packing ring arranged between the bearing surfaces of the members, a solid ring engaging the'fiexible 'ring to maintain the same in position, and

means whereby fluid is delivered to and allowed to discharge from the chamber.

In testimony whereof, I have signed/my name to this specification, in presence of two 7 subscribing witnesses.

CLINTON 0. DE WITT.

Witnesses: f

M. P. SMITH, E. L. WALLACE. 

